; Hello world.asm
; This SimpSim assembly language program prints out a simple message.
; It demonstrates:
;     assembling into machine language
;     program and data segments in memory
;     printing (using RF)
;     direct, immediate, and indirect loads
;     conditional and unconditional jumps with labels
;     integer addition
;     halting
;     integer and string data bytes

         load    R1,Text     ;the start of the string
         load    R2,1        ;increase step
         load    R0,0        ;string-terminator
NextChar:load    RF,[R1]     ;get character and print it on screen
         addi    R1,R1,R2    ;increase address
         jmpEQ   RF=R0,Ready ;when string-terminator, then ready
         jmp     NextChar    ;next character
Ready:   halt

org 20h ;; Data segment begins at 0x20
Text:    db      10
         db      "Hello world !!",10
         db      "    from the",10
         db      "  Simple Simulator",10
         db      0           ;string-terminator